mic michael fabley



(No Model.)

M. TARLBY; INSTRUMENT FOR VSUPNETLING INAGGESSIBLB HEIGHTS, am.

No. 288,321. PatentedsNov.13,1883.

MTA/55555. IN VEN T0 R o spective of my invention complete.

. y .u UNrTEE STATES PATEAVI GEEICJE.

MICHAEL EAELEY, OE PORTLAND, OREGON.

INSTRUMENTFO'R SURVEYING 'INACCESSIBLE HEIGHTS, sapo.

`JPCIFICATIN,forming part1of Letters Patent No. 288,321, dated Novemberl", 1883,

` Application filed April 3l), 1883. (No model.)

5 and State of Oregon, have invented certain new and useful Improvementsin Instruments `for Surveying Inaccessilole` Heights and Dis tances ofObjects, of which rthe following is a specication. i

My invention relates to a surveying-instru nient which can be usedeither to ascertain the altitude of inaccessibleheights or the distancesof inaccessible objects, whether on a horizontal plane or vertical`height or depth. It is 1,5 especially adapted forisurveying distancesacross rivers, Sac., the height of mountains, or the depth of caons, orother ydeclivities incapable of being traversed in order to actuallymeasure. In calculating railroad grades 2O through rough countries itwill be found very useful, and sufiiciently accurate` in all such uses,and will obviate the necessity of triangulating and iiguring out theresult, saving labor and mathematicalcalculation; and my inventionconsists in constructing a main arm or base-line, with suitablegraduations of scale thereon, andpermanently attachingthereto aquadrantfof `a circle suitably scaled to show the degrees thereon. Uponthis main arm are 3o two common spirit-levels let into its surface above`and below, and it is further .provided with sights ateach end. Uponthis main arm upon the permanently-'attached quadrant is pivoted `anangle-arm, its end upon the quad- 3 5 rant being in the forni of anindicator to show 4o being provided'witha gib andthumb-screw.

Upon this half-circleis another anglear1n,its end upon the khalf-circlealso ending in an indicator-point, to show the degree of angle, and hasa thumb-screw to hold it stationary when 4 5 the proper angle isattained. The angle-arms are marked with graduated scale, and are bothprovided with sights.

In theaccompanying drawings, forming part of this specication, Figure lis aview in per- Fig. 2 is a view of my invention when adapted tocalculate the distance of an object in ahorizontal plane, lookingthrough the sights of the anglearms. Fig. 3 is a vienr showing the mainarm in horizontal plane, but the angle-ar1ns invertical plane, `tomeasure a depth.` Fig. et is a view of my invention when arrangedtoascertain the vertical height of an obj ect, and Fig. 5 is a, sectionalview of the main arm and a clamp by which it may beattached and heldsolid while being used.

A in Fig. l represents the main arm or base-line. B is the quadrant,permanently located thereon. b b are sights, one on each end of arm A. CC arel spirit-levels let into the surface of A. B is the semi or half ofa circle. It is attached upon a clamp, E, (shown in Figs. 2 and 3,)which clamp E is provided with a gib and set-screw, c, and adaptedtomove upon arm A, when desired, the set-screw`c` making it fast when theproper distance from quadrant B is attained. D D are the` twoangle-arms. rlhey are constructed, as shown, with graduated scale upontheir upper faces and sights, d d d d, and are pivoted upon the quadrantB and semicircle B', so that their pointed ends F. F/ may indicate thedegree of angle. They are held at the proper angle by means ofthumb-screws e e', the lower surface of semicircle and quadrant restsupon the Agraduated surface of arm A, the head of thumb-screw e ofangle-arm Dbeing countersunk into the under surface of" semicircle B, sothat the semicircle B and clamp E can slide upon arrn- A; and Fis aniron clamping device, its end beingin form of a wood-screw, which isused to `fasten the entire `device and hold it in the desired positionon a log, fence, or other rest. It has 'assit-screw, f, to fasten itsecurely to the arm A.

My invention may be made of brass 'or other suitable metal, or ofrubber, and the operati-on ofmy inventionis as follows: When it isdesired to ascertain the distance of some inaccessible object, as a treeor mark across a river, then the instrument will be held in ahorizontalplane, and the operator will sight through the sights d d d d,pivotingthe'angle-arms D D until they converge upon the object, when theindicators E `E will show the degree of angle, and the basearn1A willshowthe distance of the base of the angle, while the anglearms IOO -tain the depth of any descent, ravine, caon,

&c. then the instrument will be reversed from the position Vin which itis held when ascertaining a height' and an angle of depression formed.The spirit -levels C in the arm A provide a sure means of ascertainingthe correct angle, in combination with the quadrants B B'.

Having described my invention, what I claim as new, and desire to secureby Letters Patent, 1s-

1. In an instrument for surveying inaccessible distances or heights, themain arm or base-line A, provided with a graduated scale, andhaving aquadrant of a circle, B, located uponits' graduated surface, incombination with angle-arm D, pivoted upon arm A, anglearm D', clamp E,set-screw c, and half-circle B', adapted to move upon arm A, saidanglearm D' being pivoted, and both D and D' having suitably graduatedscale of measurement upon their upper surface, operating as shown, andfor the purpose described.

2. The herein-described surveying-instrument, consisting of main arm A,constructed with spirit-levels C C and sights b, Aquadrant B, incombination with the clamp E, having setscrew c, and half-circle B',adapted to be moved along arm A, the angle-arm D, pivoted upon quadrantB, whereby its point E' will indicate the degree of angle, and angle-armD', pivoted upon half-circle B', whereby its Vpoint E' will indicate thedegree of angle, and set-screws e e', substantially as herein shown anddescribed.

MIGHAEL HARLEY.

Witnesses:

F. B. VVINTnRs, E. W, MoRRIsoN.y

